The primary objective of this program is to minimize or eliminate radiation injury to the small bowel during high dose pelvic irradiation. The effort is specifically directed towards application to preoperative high dose adjuvant irradiation in the treatment of high-stage, non-metastatic bladder cancer. The approach is a method that mechanically displaces the small bowel from the field of irradiation, during the period of radiation delivery. The proposed method involves the insertion of a inflatable, biologically inert (silastic) space-occupying device into the pelvis and lower abdominal cavity. At the same procedure, urinary diversion would be accomplished with an ileal-loop (high). During a subsequent course of 6000 Mev irradiation, the silastic device would prevent small bowel, cecum, and sigmoid colon from entry into the irradiation field. Following the course of radiotherapy a second operative procedure would be undertaken at which time the device would be removed and cystectomy performed.